From 07256dc046b1be329940f9516c0ae74eec09a9f0 Mon Sep 17 00:00:00 2001 From: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Date: Wed, 27 Sep 2023 15:06:41 -0400 Subject: [PATCH] drm/amd/display: Don't use fsleep for PSR exit waits [ Upstream commit 79df45dc4bfb13d9bd3a75338b9d9dab948be3d6 ] [Why] These functions can be called from high IRQ levels and the OS will hang if it tries to use a usleep_highres or a msleep. [How] Replace the fsleep with a udelay. Reviewed-by: Aric Cyr <aric.cyr@amd.com> Acked-by: Tom Chung <chiahsuan.chung@amd.com> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c | 3 ++- drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c b/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c index 63009db8b5a7..d156eeef466f 100644 --- a/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c @@ -586,7 +586,8 @@ static void dcn10_dmcu_set_psr_enable(struct dmcu *dmcu, bool enable, bool wait) if (state == PSR_STATE0) break; } - fsleep(500); + /* must *not* be fsleep - this can be called from high irq levels */ + udelay(500); } /* assert if max retry hit */ diff --git a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c index 0f24b6fbd220..4704c9c85ee6 100644 --- a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c +++ b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c @@ -216,7 +216,8 @@ static void dmub_psr_enable(struct dmub_psr *dmub, bool enable, bool wait, uint8 break; } - fsleep(500); + /* must *not* be fsleep - this can be called from high irq levels */ + udelay(500); } /* assert if max retry hit */ -- GitLab